Process of refining sugar.



H. WIESE.

PROCESS OF REFINING SUGAR.

APPLICATION FILED 5mm, 1012.

Patented Mar.26, 1912.

a w T D W U 1 HERMANN WIESE, 0F WALLAGEBURG,- ONTARIO, CANADA.

PROCESS OF REFINING- SUGAR.

Specification of Letters Patent.

Patented Mar. 26, 1912.

Application filed January 9, 1912. Serial No. 670,169.

To all whom it may concern Be it known that I, HERMANN russ, a subject of the Emperor of Germany, residing at ,Wallaceburg, in the Province of Ontario and Dominion of Canada, have in vented certain new-and useful Improvements in. Processes of Refining Sugar, of which the following is a specification, refer-' ence being had therein to the accompanying drawings.

The invention relates to process for the refining of sugar andvhas for its primary object a reduction in the time required for extracting sugar from the syrup.

It is a further object to obtain a higher degree of extraction, that is, to obt'aina greater quantity of the sugar with a residuum molasses of lower grade or having a smaller percentage of sugar therein.

Still another object of the invention is to simplify and reduce the cost of apparatus required for the extraction process and to greatly economize in space required for such ap aratus. y.

ith these objects in view the invention consists in the process as hereinafter set forth. i

In the drawings,Figure 1 shows diagrammatically the apparatus which may be used in carrying on my improved process. Fig. 2 is a plan of a modified device for mechanically agitating themass.

caramel.

In the present state of the art it is usual to concentrate the sugar juices for the initial crystallization of the sugar in vacuum pans. This concentration is however, only continued to obtain from 90 to 94% of dry substance and the further crystallization is carried on outside of the pans. It usually requires from 2 4 to 72 hours treatment in the vacuum pan with a stirring and cooling period of from 3 to 6 days in the crystallizers or mixers. Furthermore, the mother syrup or molasses is only reduced to about purity and the fillmasscs are exposed to high temperatures for a considerable period of time, resulting in the destruction of a portion of the sugar and the formation of The long time required by the process and particularly while in the crystallizers, necessitates apparatus of large capacity, which not only means higlicost of installation but also requires'a great deal of valuable space.

With my improved process the. time required for the concentration of the juice to a degree of from 95 to 96%of dry substance, and the complete extraction of the crystallizable sugar is only from 18 to 30 hours. Furthermore, the whole process is carried out in the vacuum pan which dispenses with the crystallizers, thereby diminishing the cost of the apparatus and greatly economizing in space. Still another advantage of my. improved process is that the residuum molasses is of lower grade. which means that sugar which is present in the high grade molasses has been extracted.

In detail, the sugar juices or syrups are first introduced. into the vacuum pan such as A and are boiled down preferably under high vacuum until graining is effected, the temperature being preferably from 72 to 80% 0. according to the purity of the juices or syrup, the higher the purity of the juices the lower the temperature. As soon as a sutlicient quantity of sugar grain ofa proper size is obtained the boiling temperature is reduced slowly a few degrees and care is taken to avoid the boiling together of the mass. An additional quantity of syrup or juice is then introduced in the pan which is regulated to avoid too great a thinning of the fluid, the density required varying according to the purity-of juice or syrup. It is desirable to avoid too sudden a change in temperature which in this stage of the process should be maintained from 68 to 72 C; After graining, fresh-syrup or juice is again introduced and the same process is repeated until the limit of capacity of the pan is reached, the successive drafts of syrup or juice are preferably equal in quantity and as before stated, the temperature is regulated to avoid sudden changes. After the concentration of the last draft of syrup or juice in the pan the so-called boiling together is begun, maintaining the same temperature, and when the fillmass acquires a density at which in the previous treatment, fresh juice or syrup is introduced, the vacuum in the pan is slightly raised with the resulting reduction in temperature. The circulation is increased by the increase of vacuum, giving the mother syrup an opportunity to give up all its crystallizablc sugar and to enlarge the crystals already made. This treatment is continued as long as the natural circulation of the mass may be maintained, any reduction of which is indicated by a rise in they temperature. If the natural circulation of the mass should cease, mechanical agitation of the mass is then begun, preferably by stirrers B which are arranged in the vacuum pan and which when .in action continue the circulation and agitation of the mass. Thus a concentration from 94 to 96.5% of dry substance is obtained. At the completion of the boiling the temperature will be about 65 C. and after the steam in the heating coils C is shut-off the mechanical agitation is continued and the same vacuum is maintained. The temperature is permitted to drop and the cooling is preferably assisted by the circulation of cold water from a tank D through the coil C and in this way practically all of the cryst-allizable sugar is extracted from the mother syrup. Thus the purity of residuum molasses is 60% or under, whereas in processes heretofore used it was of higher grade.

. In place of the stirring device illustrated in Fig. 1, I may substitute the means shown in Fig. 2 which E is a perforated conduit arranged in the lower part of the vacuum pan and connected with a source of air not a vacuum pan to a density of under 94% of dry substance, and in then continuing the concentration while the mass is still in the vacuum pan by forced circulation to a density from 94 to 96%.'

2. The process of extracting sugar from. uice or syrup which consists in concentratperature between 72 and 80 0., varying ac-.

cording to purity of the syrup and highest at the lowest purity, in then continuing the concentration under reduced temperature and increased vacuum until the limit of in then mechanically agitating the mass while still in the vacuum pan and further reducing the temperature until a concentration of from 94 to 96.5% dry substance is obtained.

4. The process of extracting sugar from juice or syrup which consists in concentrating and'graining successive drafts of the juice or syrup in a vacuum pan to a degree of under 94% dry substance, in then continuing the concentration of the whole mass under increased vacuum and lower te1nperatur'e until the limit of natural circulation is reached, in then further continuing the concentration under forced circulation,. and in then cooling and continuing the forced circulation or agitation, all of said operations beingperfor'med in the vacuum pan.

In testimony whereof I affix my signaturein presence of two witnesses.

HERMANN WIESE. Witnesses:

JAMES P. BARRY, DELBERT COLLINS.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

' Washington, D. G.

' natural circulation of the mass is attained, 

